SlideShare a Scribd company logo
BENIGN EEG VARIANTS
(spot)
DR SWAPNIL SAMADHIYA
SR DM NEUROLOGY
GMC KOTA
Wicket waves
• Short runs of 6-11Hz spikes, sometimes single spike
– usually within alpha frequency range
• Monophasic arciform waveforms (60-200uV)
• Anterior or mid-temporal region
– Usually unilaterally,shifting emphasis between sides
• Sharp monophasic, no slow wave
• Present in relaxed wakefulness, drowsiness, light sleep
• Usually in middle and late adulthood
• Clinical significance: analogue of the auditory alpha rhythm
– May decrease with auditory stimulation
– Not associated with epilepsy
Benign Sporadic Sleep Spikes
BETS–Benign Epileptiform Transients of Sleep
• Occur in light sleep (non-REM 1 and 2 sleep)
• Amplitude of <50 microV and duration of <50 ms
• Usually monophasic, occasionally diphasic
• Located temporal uni- or bilateral
• Incidence of 20%
• Small sharp spikes are not associated with epilepsy
6 per second spike-waves
(Phantom Spike and Wave)
• Brief bursts of low amplitude spike-and-slow wave 6Hz (5-
7Hz)
• Spike often not clearly discernible: “phantom”
• Bilateral and synchronous
• Maximal at midline (posterior or anterior)
• Relaxed wakefulness and drowsiness
• Adolescents and young adults
• Duration of 1-2 seconds
14 & 6 Hz positive spikes
• Bursts of 14Hz (13-17) or 6Hz (5-7)
• Duration: 0.5-1 second
• Unilateral (R>L) or bilateral asynchronous or synchronous
• Arch-shaped waves / Positive sharp peaks
• Maximum in posterior temporal region
• Present in drowsiness and light sleep
• Young adults
Rhythmic Temporal Theta of Drowsiness
(Psychomotor Variant)
• Trains of rhythmic theta waves 5-7Hz
• Duration 5-10sec
• Located in midtemporal region
• Often unilateral
• May be bisynchronous, with shifting asymmetry between sides
• Present in relaxed wakefulness and drowsiness
• Adolescents and adults
Subclinical Rhythmic Electrographic
Discharge of Adults (SREDA)
• Abrupt onset and termination of sharp rhythmic theta rhythm of
5-7Hz
• Constant frequency
• Duration of 40-80 sec
• Located Parietal and Posterior temporal
• Bilateral and synchronous, symmetrical (however sometimes
unilateral)
• No change in localization of frequency
• Present in wakefulness, drowsiness, stage II sleep
• Trigger: Hyperventilation
• Usually in people >50 years
• Uncommon (incidence <0.05%)
POSTS(Positive Occipital Sharp
Transients of Sleep)
• Located in the occipital regions bilaterally as positive waves, during
drowsiness/sleep
• Triangular in shape (like the capital lambda: Λ, only upside down) and
generally symmetric.
• Most evident in non-REM 1 and non-REM 2
• Amplitude 20 - 75 μV and may be as high as 120 μV, duration 80 to
200 ms
• Same morphology as Lambda waves, both in form and in occipital
distribution(lambda waves are during awake state, when visually
fixating).
• POSTS are completely normal, should not be confused with spikes
Lambda
• Located in the occipital regions bilaterally as positive
waves.
• Triangular in shape (like the capital lambda: Λ) and
generally symmetric.
• Amplitude: 50 microV
• Duration 200-300 msec
• Present with eyes opened and during visual fixation
• Same morphology as POSTS (Positive occipital sharp
transients of sleep), both in form and in occipital
distribution, however POSTS are during sleep.
MU
• Frequency: 8-12 Hz
• More sharply than Alpha rhythm
• Most prominent in central regions
• Frequency asymmetry of >1 Hz is abnormal
• Mu rhythm is suppressed by contralateral opening and closing
of the fist.
Vertex sharp wave
• Generally diphasic ,sharply contoured.
• Maximum amplitude at C3 & C4 lasting upto 200 ms.
• Initial deflection surface negative f/b slower & lower voltage positive
wave.
• Maximum at the vertex (like K complex)
• Amplitude: 50-150 microV
• Presence in non-REM 1 and to a lesser extent in non-REM 2
• Narrower and more focal than K complex
• Unlike K complex vertex waves are not associated with sleep spindles
.
K Complex & Sleep Spindle
• Presence in Non-REM 2 sleep
• High amplitude (>100 microV)
• Long duration (>200ms)
• Diphasic
• Broad field that phase reverses in the vertex region.
• Often associated with sleep spindles
• Location: Frontocentral with the maximum at Cz or Fz.
Alpha variants
• Appears in the occipital regions at a frequency onehalf that of the
ongoing PDR
• Suspect its presence when PDR activity has a notched appearance,
revealing its subharmonic relationship
• Slow alpha variant has the same characteristics as the PDR itself – for
example, it attenuates with eye opening.
• Fast alpha variant also appears in the occipital areas and has a
frequency twice that of the PDR.
• These variants may alternate with the PDR, or the PDR may not
be present at all
Posterior slow wave of youth
• Occur amid the alpha rhythm (AR) and are evident because of their
longer wave duration.
• Have a posterior field ,maximal at the occipital poles, present only
in relaxed wakeful states with eyes closed.
• Evident with bipolar montages, sometimes better seen with longer
interelectrode distances.
• Occipital and central electrodes depict PSWY well
• The wave polarity is inconsistent and the wave duration typically
ranges from 0.3 to 0.5 seconds
• Most commonly, PSWY appear as sporadic, interspersed slow waves
• PSWY usually are symmetric and bisynchronous across the
occiput but may occur with minor lateralization, which is typically
toward the right
Mittens
• Produced through the partial superimposition of a sharp wave on
the up slope of a following slow wave of the same polarity.
• Overlap produces a notching in the slow wave that divides the
slow wave into two compartments, which are a smaller and sharper
thumb compartment, and then a larger and rounder hand
compartment
• Centered in the frontal-central midline with extension into the
parasagittal regions bilaterally and possible inclusion of the parietal
region also.
• The duration - 400 to 500 ms and amplitude is high.
• The pattern emerges out of anterior, polymorphic delta activity of
deep sleep.
Frontal arousal rhythm
• Trains of 7- 10Hz monomorphic, symmetrical waveforms
• Duration: <20sec
• Localisation: Frontal regions.
• Occurs in children following arousal from sleep
• Disappears once child is fully awake
• NOT to be confused with frontal arousal rhythm in the theta
range described by Hughes
The 7-Hz Cigánek rhythm is sustained through the first three occurrences of eye blink artifact and then ends
with the fourth eye blink and increase in muscle artifact. The combination of eye blink and increased muscle
artifact indicates an increase in wakefulness, which is a state change that can diminish a Cigánek rhythm.
Midline theta rhythm(Ciganek)
• Rhythmic train of 5-7Hz (6Hz)
• Duration: <20sec
• Smooth, sinusoidal, arch-like, spiky appearance (>50uV)
• Amplitude waxes and wanes
• Vertex (Cz)
– Fz > Pz >> parasagittal electrodes
• Wakefulness (concentration) and drowsiness
• Children and adults
• Not associated with epilepsy
References
• Rowan’s PRIMER of EEG,Second Edition
• Atlas of EEG Patterns (Stern&Engel),Second
Edition, LIPPINCOTT WILLIAMS & WILKINS
Thank you

More Related Content

What's hot

Posterior slow waves of youth
Posterior slow waves of youthPosterior slow waves of youth
Posterior slow waves of youth
Mohibullah Kakar
 
Principles of polarity in eeg
Principles of polarity in eegPrinciples of polarity in eeg
Principles of polarity in eeg
Pramod Krishnan
 
EEG Variants with patterns by Murtaza Syed
EEG Variants with patterns by Murtaza SyedEEG Variants with patterns by Murtaza Syed
EEG Variants with patterns by Murtaza Syed
Murtaza Syed
 
Abnormal EEG patterns
Abnormal EEG patternsAbnormal EEG patterns
Abnormal EEG patterns
Faizan Abdullah
 
Normal EEG waveforms.pptx
Normal EEG waveforms.pptxNormal EEG waveforms.pptx
Normal EEG waveforms.pptx
budhial balaji
 
Normal EEG patterns, frequencies, as well as patterns that may simulate disease
Normal EEG patterns, frequencies, as well as patterns that may simulate diseaseNormal EEG patterns, frequencies, as well as patterns that may simulate disease
Normal EEG patterns, frequencies, as well as patterns that may simulate disease
Rahul Kumar
 
EEG Generators
EEG GeneratorsEEG Generators
EEG Generators
Rahul Kumar
 
Lambda waves
Lambda wavesLambda waves
Lambda waves
Mohibullah Kakar
 
Non epileptiform variants in EEG.pptx
Non epileptiform variants in EEG.pptxNon epileptiform variants in EEG.pptx
Non epileptiform variants in EEG.pptx
Pramod Krishnan
 
Sleep activity in eeg
Sleep activity in eegSleep activity in eeg
Sleep activity in eeg
Mohibullah Kakar
 
Periodic lateralized epileptiform discharges
Periodic lateralized epileptiform dischargesPeriodic lateralized epileptiform discharges
Periodic lateralized epileptiform discharges
Manideep Malaka
 
Sleep EEG
Sleep EEGSleep EEG
Sleep EEG
NeurologyKota
 
Eeg wave pattern
Eeg wave patternEeg wave pattern
Eeg wave pattern
Roopchand Ps
 
Blink H reflex SFEMG.pptx
Blink H reflex SFEMG.pptxBlink H reflex SFEMG.pptx
Blink H reflex SFEMG.pptx
NeurologyKota
 
EEG Artifact and How to Resolve
EEG Artifact and How to ResolveEEG Artifact and How to Resolve
EEG Artifact and How to Resolve
Lalit Bansal
 
Generalised periodic epileptiform discharges
Generalised periodic epileptiform dischargesGeneralised periodic epileptiform discharges
Generalised periodic epileptiform discharges
Pramod Krishnan
 
Eeg artifacts and benign variants
Eeg artifacts and benign variantsEeg artifacts and benign variants
Eeg artifacts and benign variantsRoopchand Ps
 
REPETITIVE NERVE STIMULATION (RNS)
REPETITIVE NERVE STIMULATION (RNS)REPETITIVE NERVE STIMULATION (RNS)
REPETITIVE NERVE STIMULATION (RNS)
Dhaval Modi
 

What's hot (20)

Posterior slow waves of youth
Posterior slow waves of youthPosterior slow waves of youth
Posterior slow waves of youth
 
Principles of polarity in eeg
Principles of polarity in eegPrinciples of polarity in eeg
Principles of polarity in eeg
 
EEG Variants with patterns by Murtaza Syed
EEG Variants with patterns by Murtaza SyedEEG Variants with patterns by Murtaza Syed
EEG Variants with patterns by Murtaza Syed
 
Abnormal EEG patterns
Abnormal EEG patternsAbnormal EEG patterns
Abnormal EEG patterns
 
Normal EEG waveforms.pptx
Normal EEG waveforms.pptxNormal EEG waveforms.pptx
Normal EEG waveforms.pptx
 
Normal EEG patterns, frequencies, as well as patterns that may simulate disease
Normal EEG patterns, frequencies, as well as patterns that may simulate diseaseNormal EEG patterns, frequencies, as well as patterns that may simulate disease
Normal EEG patterns, frequencies, as well as patterns that may simulate disease
 
EEG Generators
EEG GeneratorsEEG Generators
EEG Generators
 
Lambda waves
Lambda wavesLambda waves
Lambda waves
 
Non epileptiform variants in EEG.pptx
Non epileptiform variants in EEG.pptxNon epileptiform variants in EEG.pptx
Non epileptiform variants in EEG.pptx
 
Sleep activity in eeg
Sleep activity in eegSleep activity in eeg
Sleep activity in eeg
 
Periodic lateralized epileptiform discharges
Periodic lateralized epileptiform dischargesPeriodic lateralized epileptiform discharges
Periodic lateralized epileptiform discharges
 
Artifacts in eeg final
Artifacts in eeg finalArtifacts in eeg final
Artifacts in eeg final
 
Sleep EEG
Sleep EEGSleep EEG
Sleep EEG
 
Eeg wave pattern
Eeg wave patternEeg wave pattern
Eeg wave pattern
 
Blink H reflex SFEMG.pptx
Blink H reflex SFEMG.pptxBlink H reflex SFEMG.pptx
Blink H reflex SFEMG.pptx
 
EEG Artifact and How to Resolve
EEG Artifact and How to ResolveEEG Artifact and How to Resolve
EEG Artifact and How to Resolve
 
Generalised periodic epileptiform discharges
Generalised periodic epileptiform dischargesGeneralised periodic epileptiform discharges
Generalised periodic epileptiform discharges
 
Eeg artifacts and benign variants
Eeg artifacts and benign variantsEeg artifacts and benign variants
Eeg artifacts and benign variants
 
REPETITIVE NERVE STIMULATION (RNS)
REPETITIVE NERVE STIMULATION (RNS)REPETITIVE NERVE STIMULATION (RNS)
REPETITIVE NERVE STIMULATION (RNS)
 
EEG artifacts
EEG artifactsEEG artifacts
EEG artifacts
 

Similar to Benign variants in eeg

Normal eeg variants by faizan abdullah
Normal eeg variants by faizan abdullahNormal eeg variants by faizan abdullah
Normal eeg variants by faizan abdullah
Faizan Abdullah
 
EEG basic to practice 2
EEG basic to practice 2EEG basic to practice 2
EEG basic to practice 2
Mohamed Mahdy
 
EEG dr archana
EEG dr archanaEEG dr archana
EEG dr archana
dr archana verma
 
EEG Variants By IM
EEG Variants By IMEEG Variants By IM
EEG Variants By IM
Murtaza Syed
 
EEG in Sleep
EEG in Sleep EEG in Sleep
EEG in Sleep
Rahul Kumar
 
EEG of Children and Sleep
EEG of Children and Sleep EEG of Children and Sleep
EEG of Children and Sleep
Sanjida Ahmed
 
Approaching the eeg
Approaching the eegApproaching the eeg
Approaching the eeg
rzgar hamed
 
EEG Lecture 2.pptx
EEG Lecture 2.pptxEEG Lecture 2.pptx
EEG Lecture 2.pptx
munnam37
 
Obstructive sleep apnea and snoring (OSA)
Obstructive sleep apnea and snoring (OSA) Obstructive sleep apnea and snoring (OSA)
Obstructive sleep apnea and snoring (OSA)
mac os
 
Sleep stages
Sleep stagesSleep stages
Sleep stages
Dr.Jeet Nadpara
 
Eeg maturation
Eeg maturationEeg maturation
Eeg maturation
AliMohammedMohammed
 
Sleep Physiology and Disorders Arpit
Sleep Physiology and Disorders  ArpitSleep Physiology and Disorders  Arpit
Sleep Physiology and Disorders Arpit
Arpit Koolwal
 
Physiology of sleep and E.E.G for undergraduates
Physiology of sleep and E.E.G for undergraduatesPhysiology of sleep and E.E.G for undergraduates
Physiology of sleep and E.E.G for undergraduates
Mohamed Abdelghani
 
eeg ppt defining all aspects of eeg and various type of waves seen in every e...
eeg ppt defining all aspects of eeg and various type of waves seen in every e...eeg ppt defining all aspects of eeg and various type of waves seen in every e...
eeg ppt defining all aspects of eeg and various type of waves seen in every e...
AdityaRahane7
 
چرخه های زیستی و خواب
چرخه های  زیستی  و خوابچرخه های  زیستی  و خواب
چرخه های زیستی و خواب
Zeinab alimadadi
 
Pediatric EEG.pptx
Pediatric EEG.pptxPediatric EEG.pptx
Pediatric EEG.pptx
DanishAhammed6
 
Recognition of abnormal EEG.
Recognition of abnormal EEG.Recognition of abnormal EEG.
Recognition of abnormal EEG.
Shehzad Hussain Raja
 
normal eeg
 normal eeg  normal eeg
normal eeg
Sachin Adukia
 

Similar to Benign variants in eeg (20)

Normal eeg variants by faizan abdullah
Normal eeg variants by faizan abdullahNormal eeg variants by faizan abdullah
Normal eeg variants by faizan abdullah
 
EEG basic to practice 2
EEG basic to practice 2EEG basic to practice 2
EEG basic to practice 2
 
EEG dr archana
EEG dr archanaEEG dr archana
EEG dr archana
 
EEG Variants By IM
EEG Variants By IMEEG Variants By IM
EEG Variants By IM
 
EEG in Sleep
EEG in Sleep EEG in Sleep
EEG in Sleep
 
EEG of Children and Sleep
EEG of Children and Sleep EEG of Children and Sleep
EEG of Children and Sleep
 
Approaching the eeg
Approaching the eegApproaching the eeg
Approaching the eeg
 
EEG Lecture 2.pptx
EEG Lecture 2.pptxEEG Lecture 2.pptx
EEG Lecture 2.pptx
 
Obstructive sleep apnea and snoring (OSA)
Obstructive sleep apnea and snoring (OSA) Obstructive sleep apnea and snoring (OSA)
Obstructive sleep apnea and snoring (OSA)
 
Eeg
Eeg Eeg
Eeg
 
Sleep stages
Sleep stagesSleep stages
Sleep stages
 
Eeg maturation
Eeg maturationEeg maturation
Eeg maturation
 
Sleep Physiology and Disorders Arpit
Sleep Physiology and Disorders  ArpitSleep Physiology and Disorders  Arpit
Sleep Physiology and Disorders Arpit
 
Physiology of sleep and E.E.G for undergraduates
Physiology of sleep and E.E.G for undergraduatesPhysiology of sleep and E.E.G for undergraduates
Physiology of sleep and E.E.G for undergraduates
 
eeg ppt defining all aspects of eeg and various type of waves seen in every e...
eeg ppt defining all aspects of eeg and various type of waves seen in every e...eeg ppt defining all aspects of eeg and various type of waves seen in every e...
eeg ppt defining all aspects of eeg and various type of waves seen in every e...
 
چرخه های زیستی و خواب
چرخه های  زیستی  و خوابچرخه های  زیستی  و خواب
چرخه های زیستی و خواب
 
Pediatric EEG.pptx
Pediatric EEG.pptxPediatric EEG.pptx
Pediatric EEG.pptx
 
Normal awake and sleep EEG
Normal awake and sleep EEGNormal awake and sleep EEG
Normal awake and sleep EEG
 
Recognition of abnormal EEG.
Recognition of abnormal EEG.Recognition of abnormal EEG.
Recognition of abnormal EEG.
 
normal eeg
 normal eeg  normal eeg
normal eeg
 

More from NeurologyKota

CONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptx
CONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptxCONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptx
CONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptx
NeurologyKota
 
NEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptx
NEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptxNEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptx
NEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptx
NeurologyKota
 
LOCALISATION OF LESION CAUSING COMA.pptx
LOCALISATION OF LESION CAUSING COMA.pptxLOCALISATION OF LESION CAUSING COMA.pptx
LOCALISATION OF LESION CAUSING COMA.pptx
NeurologyKota
 
TREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptx
TREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptxTREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptx
TREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptx
NeurologyKota
 
REMOTE ROBOTIC.pptx
REMOTE ROBOTIC.pptxREMOTE ROBOTIC.pptx
REMOTE ROBOTIC.pptx
NeurologyKota
 
DUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptx
DUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptxDUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptx
DUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptx
NeurologyKota
 
SMART WEARABLE DEVICES IN NEUROLOGY new.pptx
SMART WEARABLE DEVICES IN NEUROLOGY new.pptxSMART WEARABLE DEVICES IN NEUROLOGY new.pptx
SMART WEARABLE DEVICES IN NEUROLOGY new.pptx
NeurologyKota
 
ASSESSMENT OF AUTONOMIC FUNCTION TEST.pptx
ASSESSMENT OF AUTONOMIC FUNCTION TEST.pptxASSESSMENT OF AUTONOMIC FUNCTION TEST.pptx
ASSESSMENT OF AUTONOMIC FUNCTION TEST.pptx
NeurologyKota
 
TRANSCRANIAL DOPPLER (1).pptx
TRANSCRANIAL DOPPLER (1).pptxTRANSCRANIAL DOPPLER (1).pptx
TRANSCRANIAL DOPPLER (1).pptx
NeurologyKota
 
INTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptx
INTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptxINTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptx
INTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptx
NeurologyKota
 
CAROTID WEB.pptx
CAROTID WEB.pptxCAROTID WEB.pptx
CAROTID WEB.pptx
NeurologyKota
 
CNS IRIS.pptx
CNS IRIS.pptxCNS IRIS.pptx
CNS IRIS.pptx
NeurologyKota
 
EPILEPTIC ENCEPHALOPATHY
 EPILEPTIC ENCEPHALOPATHY  EPILEPTIC ENCEPHALOPATHY
EPILEPTIC ENCEPHALOPATHY
NeurologyKota
 
Domain Assessment in Dementia.pptx
Domain Assessment in Dementia.pptxDomain Assessment in Dementia.pptx
Domain Assessment in Dementia.pptx
NeurologyKota
 
Young Onset Dementia.pptx
Young Onset Dementia.pptxYoung Onset Dementia.pptx
Young Onset Dementia.pptx
NeurologyKota
 
ENCEPHALOPATHY
ENCEPHALOPATHY ENCEPHALOPATHY
ENCEPHALOPATHY
NeurologyKota
 
NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER
NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER
NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER
NeurologyKota
 
Hyperthermic syndrome in ICU and their management.pptx
Hyperthermic syndrome in ICU and their management.pptxHyperthermic syndrome in ICU and their management.pptx
Hyperthermic syndrome in ICU and their management.pptx
NeurologyKota
 
Entrapment Syndromes of Lower Limb.pptx
Entrapment Syndromes of Lower Limb.pptxEntrapment Syndromes of Lower Limb.pptx
Entrapment Syndromes of Lower Limb.pptx
NeurologyKota
 
MOG and IgG-4 related Neurological manifestation.pptx
MOG and IgG-4 related Neurological manifestation.pptxMOG and IgG-4 related Neurological manifestation.pptx
MOG and IgG-4 related Neurological manifestation.pptx
NeurologyKota
 

More from NeurologyKota (20)

CONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptx
CONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptxCONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptx
CONCEPT OF NODOPATHIES AND PARANODOPATHIES.pptx
 
NEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptx
NEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptxNEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptx
NEUROLOGICAL SCALES FOR ASSESSMENT OF CONSCIOUSNESS.pptx
 
LOCALISATION OF LESION CAUSING COMA.pptx
LOCALISATION OF LESION CAUSING COMA.pptxLOCALISATION OF LESION CAUSING COMA.pptx
LOCALISATION OF LESION CAUSING COMA.pptx
 
TREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptx
TREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptxTREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptx
TREADMILL For_BRAIN_Dr Bharat Bhushan sir.pptx
 
REMOTE ROBOTIC.pptx
REMOTE ROBOTIC.pptxREMOTE ROBOTIC.pptx
REMOTE ROBOTIC.pptx
 
DUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptx
DUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptxDUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptx
DUAL AND TRIPLE ANTITHROMBOTIC THERAPY FOR SECONDARY STROKE [Autosaved].pptx
 
SMART WEARABLE DEVICES IN NEUROLOGY new.pptx
SMART WEARABLE DEVICES IN NEUROLOGY new.pptxSMART WEARABLE DEVICES IN NEUROLOGY new.pptx
SMART WEARABLE DEVICES IN NEUROLOGY new.pptx
 
ASSESSMENT OF AUTONOMIC FUNCTION TEST.pptx
ASSESSMENT OF AUTONOMIC FUNCTION TEST.pptxASSESSMENT OF AUTONOMIC FUNCTION TEST.pptx
ASSESSMENT OF AUTONOMIC FUNCTION TEST.pptx
 
TRANSCRANIAL DOPPLER (1).pptx
TRANSCRANIAL DOPPLER (1).pptxTRANSCRANIAL DOPPLER (1).pptx
TRANSCRANIAL DOPPLER (1).pptx
 
INTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptx
INTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptxINTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptx
INTRACEREBRAL HEMORRHAGE IN YOUNG ADULTS.pptx
 
CAROTID WEB.pptx
CAROTID WEB.pptxCAROTID WEB.pptx
CAROTID WEB.pptx
 
CNS IRIS.pptx
CNS IRIS.pptxCNS IRIS.pptx
CNS IRIS.pptx
 
EPILEPTIC ENCEPHALOPATHY
 EPILEPTIC ENCEPHALOPATHY  EPILEPTIC ENCEPHALOPATHY
EPILEPTIC ENCEPHALOPATHY
 
Domain Assessment in Dementia.pptx
Domain Assessment in Dementia.pptxDomain Assessment in Dementia.pptx
Domain Assessment in Dementia.pptx
 
Young Onset Dementia.pptx
Young Onset Dementia.pptxYoung Onset Dementia.pptx
Young Onset Dementia.pptx
 
ENCEPHALOPATHY
ENCEPHALOPATHY ENCEPHALOPATHY
ENCEPHALOPATHY
 
NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER
NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER
NEWER INSIGHT IN FUNCTIONAL NEUROLOGICAL DISORDER
 
Hyperthermic syndrome in ICU and their management.pptx
Hyperthermic syndrome in ICU and their management.pptxHyperthermic syndrome in ICU and their management.pptx
Hyperthermic syndrome in ICU and their management.pptx
 
Entrapment Syndromes of Lower Limb.pptx
Entrapment Syndromes of Lower Limb.pptxEntrapment Syndromes of Lower Limb.pptx
Entrapment Syndromes of Lower Limb.pptx
 
MOG and IgG-4 related Neurological manifestation.pptx
MOG and IgG-4 related Neurological manifestation.pptxMOG and IgG-4 related Neurological manifestation.pptx
MOG and IgG-4 related Neurological manifestation.pptx
 

Recently uploaded

Instructions for Submissions thorugh G- Classroom.pptx
Instructions for Submissions thorugh G- Classroom.pptxInstructions for Submissions thorugh G- Classroom.pptx
Instructions for Submissions thorugh G- Classroom.pptx
Jheel Barad
 
The geography of Taylor Swift - some ideas
The geography of Taylor Swift - some ideasThe geography of Taylor Swift - some ideas
The geography of Taylor Swift - some ideas
GeoBlogs
 
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
siemaillard
 
Ethnobotany and Ethnopharmacology ......
Ethnobotany and Ethnopharmacology ......Ethnobotany and Ethnopharmacology ......
Ethnobotany and Ethnopharmacology ......
Ashokrao Mane college of Pharmacy Peth-Vadgaon
 
PART A. Introduction to Costumer Service
PART A. Introduction to Costumer ServicePART A. Introduction to Costumer Service
PART A. Introduction to Costumer Service
PedroFerreira53928
 
Digital Tools and AI for Teaching Learning and Research
Digital Tools and AI for Teaching Learning and ResearchDigital Tools and AI for Teaching Learning and Research
Digital Tools and AI for Teaching Learning and Research
Vikramjit Singh
 
Introduction to Quality Improvement Essentials
Introduction to Quality Improvement EssentialsIntroduction to Quality Improvement Essentials
Introduction to Quality Improvement Essentials
Excellence Foundation for South Sudan
 
How libraries can support authors with open access requirements for UKRI fund...
How libraries can support authors with open access requirements for UKRI fund...How libraries can support authors with open access requirements for UKRI fund...
How libraries can support authors with open access requirements for UKRI fund...
Jisc
 
Unit 2- Research Aptitude (UGC NET Paper I).pdf
Unit 2- Research Aptitude (UGC NET Paper I).pdfUnit 2- Research Aptitude (UGC NET Paper I).pdf
Unit 2- Research Aptitude (UGC NET Paper I).pdf
Thiyagu K
 
Operation Blue Star - Saka Neela Tara
Operation Blue Star   -  Saka Neela TaraOperation Blue Star   -  Saka Neela Tara
Operation Blue Star - Saka Neela Tara
Balvir Singh
 
How to Make a Field invisible in Odoo 17
How to Make a Field invisible in Odoo 17How to Make a Field invisible in Odoo 17
How to Make a Field invisible in Odoo 17
Celine George
 
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptx
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxStudents, digital devices and success - Andreas Schleicher - 27 May 2024..pptx
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptx
EduSkills OECD
 
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdf
Welcome to TechSoup   New Member Orientation and Q&A (May 2024).pdfWelcome to TechSoup   New Member Orientation and Q&A (May 2024).pdf
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdf
TechSoup
 
The Roman Empire A Historical Colossus.pdf
The Roman Empire A Historical Colossus.pdfThe Roman Empire A Historical Colossus.pdf
The Roman Empire A Historical Colossus.pdf
kaushalkr1407
 
Language Across the Curriculm LAC B.Ed.
Language Across the  Curriculm LAC B.Ed.Language Across the  Curriculm LAC B.Ed.
Language Across the Curriculm LAC B.Ed.
Atul Kumar Singh
 
Fish and Chips - have they had their chips
Fish and Chips - have they had their chipsFish and Chips - have they had their chips
Fish and Chips - have they had their chips
GeoBlogs
 
Additional Benefits for Employee Website.pdf
Additional Benefits for Employee Website.pdfAdditional Benefits for Employee Website.pdf
Additional Benefits for Employee Website.pdf
joachimlavalley1
 
Sha'Carri Richardson Presentation 202345
Sha'Carri Richardson Presentation 202345Sha'Carri Richardson Presentation 202345
Sha'Carri Richardson Presentation 202345
beazzy04
 
The approach at University of Liverpool.pptx
The approach at University of Liverpool.pptxThe approach at University of Liverpool.pptx
The approach at University of Liverpool.pptx
Jisc
 
Basic phrases for greeting and assisting costumers
Basic phrases for greeting and assisting costumersBasic phrases for greeting and assisting costumers
Basic phrases for greeting and assisting costumers
PedroFerreira53928
 

Recently uploaded (20)

Instructions for Submissions thorugh G- Classroom.pptx
Instructions for Submissions thorugh G- Classroom.pptxInstructions for Submissions thorugh G- Classroom.pptx
Instructions for Submissions thorugh G- Classroom.pptx
 
The geography of Taylor Swift - some ideas
The geography of Taylor Swift - some ideasThe geography of Taylor Swift - some ideas
The geography of Taylor Swift - some ideas
 
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 
Ethnobotany and Ethnopharmacology ......
Ethnobotany and Ethnopharmacology ......Ethnobotany and Ethnopharmacology ......
Ethnobotany and Ethnopharmacology ......
 
PART A. Introduction to Costumer Service
PART A. Introduction to Costumer ServicePART A. Introduction to Costumer Service
PART A. Introduction to Costumer Service
 
Digital Tools and AI for Teaching Learning and Research
Digital Tools and AI for Teaching Learning and ResearchDigital Tools and AI for Teaching Learning and Research
Digital Tools and AI for Teaching Learning and Research
 
Introduction to Quality Improvement Essentials
Introduction to Quality Improvement EssentialsIntroduction to Quality Improvement Essentials
Introduction to Quality Improvement Essentials
 
How libraries can support authors with open access requirements for UKRI fund...
How libraries can support authors with open access requirements for UKRI fund...How libraries can support authors with open access requirements for UKRI fund...
How libraries can support authors with open access requirements for UKRI fund...
 
Unit 2- Research Aptitude (UGC NET Paper I).pdf
Unit 2- Research Aptitude (UGC NET Paper I).pdfUnit 2- Research Aptitude (UGC NET Paper I).pdf
Unit 2- Research Aptitude (UGC NET Paper I).pdf
 
Operation Blue Star - Saka Neela Tara
Operation Blue Star   -  Saka Neela TaraOperation Blue Star   -  Saka Neela Tara
Operation Blue Star - Saka Neela Tara
 
How to Make a Field invisible in Odoo 17
How to Make a Field invisible in Odoo 17How to Make a Field invisible in Odoo 17
How to Make a Field invisible in Odoo 17
 
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptx
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxStudents, digital devices and success - Andreas Schleicher - 27 May 2024..pptx
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptx
 
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdf
Welcome to TechSoup   New Member Orientation and Q&A (May 2024).pdfWelcome to TechSoup   New Member Orientation and Q&A (May 2024).pdf
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdf
 
The Roman Empire A Historical Colossus.pdf
The Roman Empire A Historical Colossus.pdfThe Roman Empire A Historical Colossus.pdf
The Roman Empire A Historical Colossus.pdf
 
Language Across the Curriculm LAC B.Ed.
Language Across the  Curriculm LAC B.Ed.Language Across the  Curriculm LAC B.Ed.
Language Across the Curriculm LAC B.Ed.
 
Fish and Chips - have they had their chips
Fish and Chips - have they had their chipsFish and Chips - have they had their chips
Fish and Chips - have they had their chips
 
Additional Benefits for Employee Website.pdf
Additional Benefits for Employee Website.pdfAdditional Benefits for Employee Website.pdf
Additional Benefits for Employee Website.pdf
 
Sha'Carri Richardson Presentation 202345
Sha'Carri Richardson Presentation 202345Sha'Carri Richardson Presentation 202345
Sha'Carri Richardson Presentation 202345
 
The approach at University of Liverpool.pptx
The approach at University of Liverpool.pptxThe approach at University of Liverpool.pptx
The approach at University of Liverpool.pptx
 
Basic phrases for greeting and assisting costumers
Basic phrases for greeting and assisting costumersBasic phrases for greeting and assisting costumers
Basic phrases for greeting and assisting costumers
 

Benign variants in eeg

  • 1. BENIGN EEG VARIANTS (spot) DR SWAPNIL SAMADHIYA SR DM NEUROLOGY GMC KOTA
  • 2.
  • 3. Wicket waves • Short runs of 6-11Hz spikes, sometimes single spike – usually within alpha frequency range • Monophasic arciform waveforms (60-200uV) • Anterior or mid-temporal region – Usually unilaterally,shifting emphasis between sides • Sharp monophasic, no slow wave • Present in relaxed wakefulness, drowsiness, light sleep • Usually in middle and late adulthood • Clinical significance: analogue of the auditory alpha rhythm – May decrease with auditory stimulation – Not associated with epilepsy
  • 4.
  • 5. Benign Sporadic Sleep Spikes BETS–Benign Epileptiform Transients of Sleep • Occur in light sleep (non-REM 1 and 2 sleep) • Amplitude of <50 microV and duration of <50 ms • Usually monophasic, occasionally diphasic • Located temporal uni- or bilateral • Incidence of 20% • Small sharp spikes are not associated with epilepsy
  • 6.
  • 7. 6 per second spike-waves (Phantom Spike and Wave) • Brief bursts of low amplitude spike-and-slow wave 6Hz (5- 7Hz) • Spike often not clearly discernible: “phantom” • Bilateral and synchronous • Maximal at midline (posterior or anterior) • Relaxed wakefulness and drowsiness • Adolescents and young adults • Duration of 1-2 seconds
  • 8.
  • 9. 14 & 6 Hz positive spikes • Bursts of 14Hz (13-17) or 6Hz (5-7) • Duration: 0.5-1 second • Unilateral (R>L) or bilateral asynchronous or synchronous • Arch-shaped waves / Positive sharp peaks • Maximum in posterior temporal region • Present in drowsiness and light sleep • Young adults
  • 10.
  • 11. Rhythmic Temporal Theta of Drowsiness (Psychomotor Variant) • Trains of rhythmic theta waves 5-7Hz • Duration 5-10sec • Located in midtemporal region • Often unilateral • May be bisynchronous, with shifting asymmetry between sides • Present in relaxed wakefulness and drowsiness • Adolescents and adults
  • 12.
  • 13. Subclinical Rhythmic Electrographic Discharge of Adults (SREDA) • Abrupt onset and termination of sharp rhythmic theta rhythm of 5-7Hz • Constant frequency • Duration of 40-80 sec • Located Parietal and Posterior temporal • Bilateral and synchronous, symmetrical (however sometimes unilateral) • No change in localization of frequency • Present in wakefulness, drowsiness, stage II sleep • Trigger: Hyperventilation • Usually in people >50 years • Uncommon (incidence <0.05%)
  • 14.
  • 15. POSTS(Positive Occipital Sharp Transients of Sleep) • Located in the occipital regions bilaterally as positive waves, during drowsiness/sleep • Triangular in shape (like the capital lambda: Λ, only upside down) and generally symmetric. • Most evident in non-REM 1 and non-REM 2 • Amplitude 20 - 75 μV and may be as high as 120 μV, duration 80 to 200 ms • Same morphology as Lambda waves, both in form and in occipital distribution(lambda waves are during awake state, when visually fixating). • POSTS are completely normal, should not be confused with spikes
  • 16.
  • 17. Lambda • Located in the occipital regions bilaterally as positive waves. • Triangular in shape (like the capital lambda: Λ) and generally symmetric. • Amplitude: 50 microV • Duration 200-300 msec • Present with eyes opened and during visual fixation • Same morphology as POSTS (Positive occipital sharp transients of sleep), both in form and in occipital distribution, however POSTS are during sleep.
  • 18.
  • 19. MU • Frequency: 8-12 Hz • More sharply than Alpha rhythm • Most prominent in central regions • Frequency asymmetry of >1 Hz is abnormal • Mu rhythm is suppressed by contralateral opening and closing of the fist.
  • 20.
  • 21. Vertex sharp wave • Generally diphasic ,sharply contoured. • Maximum amplitude at C3 & C4 lasting upto 200 ms. • Initial deflection surface negative f/b slower & lower voltage positive wave. • Maximum at the vertex (like K complex) • Amplitude: 50-150 microV • Presence in non-REM 1 and to a lesser extent in non-REM 2 • Narrower and more focal than K complex • Unlike K complex vertex waves are not associated with sleep spindles .
  • 22.
  • 23. K Complex & Sleep Spindle • Presence in Non-REM 2 sleep • High amplitude (>100 microV) • Long duration (>200ms) • Diphasic • Broad field that phase reverses in the vertex region. • Often associated with sleep spindles • Location: Frontocentral with the maximum at Cz or Fz.
  • 24.
  • 25. Alpha variants • Appears in the occipital regions at a frequency onehalf that of the ongoing PDR • Suspect its presence when PDR activity has a notched appearance, revealing its subharmonic relationship • Slow alpha variant has the same characteristics as the PDR itself – for example, it attenuates with eye opening. • Fast alpha variant also appears in the occipital areas and has a frequency twice that of the PDR. • These variants may alternate with the PDR, or the PDR may not be present at all
  • 26.
  • 27. Posterior slow wave of youth • Occur amid the alpha rhythm (AR) and are evident because of their longer wave duration. • Have a posterior field ,maximal at the occipital poles, present only in relaxed wakeful states with eyes closed. • Evident with bipolar montages, sometimes better seen with longer interelectrode distances. • Occipital and central electrodes depict PSWY well • The wave polarity is inconsistent and the wave duration typically ranges from 0.3 to 0.5 seconds • Most commonly, PSWY appear as sporadic, interspersed slow waves • PSWY usually are symmetric and bisynchronous across the occiput but may occur with minor lateralization, which is typically toward the right
  • 28.
  • 29. Mittens • Produced through the partial superimposition of a sharp wave on the up slope of a following slow wave of the same polarity. • Overlap produces a notching in the slow wave that divides the slow wave into two compartments, which are a smaller and sharper thumb compartment, and then a larger and rounder hand compartment • Centered in the frontal-central midline with extension into the parasagittal regions bilaterally and possible inclusion of the parietal region also. • The duration - 400 to 500 ms and amplitude is high. • The pattern emerges out of anterior, polymorphic delta activity of deep sleep.
  • 30.
  • 31. Frontal arousal rhythm • Trains of 7- 10Hz monomorphic, symmetrical waveforms • Duration: <20sec • Localisation: Frontal regions. • Occurs in children following arousal from sleep • Disappears once child is fully awake • NOT to be confused with frontal arousal rhythm in the theta range described by Hughes
  • 32. The 7-Hz Cigánek rhythm is sustained through the first three occurrences of eye blink artifact and then ends with the fourth eye blink and increase in muscle artifact. The combination of eye blink and increased muscle artifact indicates an increase in wakefulness, which is a state change that can diminish a Cigánek rhythm.
  • 33. Midline theta rhythm(Ciganek) • Rhythmic train of 5-7Hz (6Hz) • Duration: <20sec • Smooth, sinusoidal, arch-like, spiky appearance (>50uV) • Amplitude waxes and wanes • Vertex (Cz) – Fz > Pz >> parasagittal electrodes • Wakefulness (concentration) and drowsiness • Children and adults • Not associated with epilepsy
  • 34. References • Rowan’s PRIMER of EEG,Second Edition • Atlas of EEG Patterns (Stern&Engel),Second Edition, LIPPINCOTT WILLIAMS & WILKINS